TCPM Working Group J. Touch
Internet Draft USC/ISI
Intended status: Proposed Standard February 25, 2013
Expires: August 2013
Shared Use of Experimental TCP Options
draft-ietf-tcpm-experimental-options-04.txt
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six
months and may be updated, replaced, or obsoleted by other documents
at any time. It is inappropriate to use Internet-Drafts as
reference material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html
This Internet-Draft will expire on August 25, 2013.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with
respect to this document. Code Components extracted from this
document must include Simplified BSD License text as described in
Touch Expires August 25, 2013 [Page 1]Internet-Draft Shared Use of Experimental TCP Options February 2013
Section 4.e of the Trust Legal Provisions and are provided without
warranty as described in the Simplified BSD License.
Abstract
This document describes how the experimental TCP option codepoints
can concurrently support multiple TCP extensions, even within the
same connection. It uses a new IANA TCP experiment identifier, and
is also robust to experiments that are not registered and those that
do not use this sharing mechanism. It is recommended for all new TCP
options that use these codepoints.
Table of Contents
1. Introduction...................................................2
2. Conventions used in this document..............................4
3. TCP Experimental Option Structure..............................4
3.1. Selecting an ExID.........................................5
3.2. Impact on TCP Option Processing...........................6
4. Reducing the Impact of False Positives.........................6
5. Migration to Assigned Options..................................7
6. Security Considerations........................................7
7. IANA Considerations............................................7
8. References.....................................................8
8.1. Normative References......................................8
8.2. Informative References....................................8
9. Acknowledgments................................................9
1. Introduction
TCP includes options to enable new protocol capabilities that can be
activated only where needed and supported [RFC793]. The space for
identifying such options is small - 256 values, of which 30 are
assigned at the time this document was published [IANA]. Two of
these codepoints are allocated to support experiments (253, 254)
[RFC4727]. These values are intended for testing purposes or anytime
an assigned codepoint is either not warranted or available, e.g.,
based on the maturity status of the defined capability (i.e.,
Experimental or Informational, rather than Standards Track).
The term "experimental TCP options" refers here to options that use
the TCP experimental option codepoints [RFC4727]. Such experiments
can be described in any type of RFC - Experimental, Informational,
etc., and are intended to be used both in controlled environments
and in are allowed in public deployments (when not enabled as
Touch Expires August 25, 2013 [Page 2]Internet-Draft Shared Use of Experimental TCP Options February 2013
default) [RFC3692]. Nothing prohibits deploying multiple experiments
in the same environment - controlled or public. Further, some
protocols are specified in Experimental or Informational RFCs, which